If you want to decide for yourself, you can consult a grassroots website that's been set up to document where Shamrock Shakes are and aren't available, with real time updates from shake-hunters ("After calling several locations in Sacramento," one poster writes, "I was told one of the Florin Road locations has them....") And if you can't get your hands on an official shake, The Takeaway's John Hockenberry and Celeste Headlee have a recipe so you can make your own.